1. Field of the Invention
The present invention concerns a method to show two different images (respectively determined from first and second image data sets) of at least one imaging modality (in particular a medical imaging modality), of the type wherein the images can be presented together on a display device with a presentation area as a fusion image or as individual images; and wherein a detection means associated with the display device detects a movement of at least one finger of a user on or in the immediate proximity of the presentation area or contact with the presentation area, and, depending on the detection, produces a change of the presentation of the fusion image, or changes between an individual presentation and fusion presentation or changes between two individual image presentations.
2. Description of the Prior Art
Fusion images are produced by a combination of two image data sets. The image data sets can originate from different and spatially separate imaging modalities (such as magnetic resonance tomography and positron emission tomography), or can originate from a combined device. It is also known, for magnetic resonance exposures, to overlay images that were acquired with different resonance frequencies atop one another as a fusion image. Overlaying images from measurements at the proton resonant frequency and the phosphorus or sodium resonant frequency is an example. The image data sets can have been acquired simultaneously or with a time offset. After a registration of the image data sets, a combined presentation as a fusion image is possible.
The combination of the different data sets is meaningful because every imaging modality has its own advantages and disadvantages, or the exposures at different resonance frequencies provide different information in the case of magnetic resonance tomography. While x-ray and computed tomography images allow a good depiction of bones, magnetic resonance tomography is superbly suited to show soft tissues. By contrast, metabolic processes can be shown particularly well by means of positron emission tomography.
In the presentation of fusion images there is a problem that an information loss occurs given an overlay of the image data, since image data from the respective component images naturally cannot be shown simultaneously at the same fusion image point. It is therefore known for a user to change the presentation type of the image by pressing a key or clicking on a control button with the mouse. Either one image data set can be masked out by this interaction, or the contrast of one or both image data sets can be varied. The necessity of making this intervention diverts the attention of user from the fusion image and a portion of the information that should be obtained by changing the presentation type is lost.